public class Exists extends Aggregate implements Negatable, Callable
operationargumentEFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, INHERITED_CONTEXT, INSPECTION_CONTEXT, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, NAVIGATION_CONTEXT, NODE_VALUE_CONTEXT, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, W3C_CONSUMING, W3C_FREE_RANGING, W3C_GROUP_CONSUMING, W3C_MOTIONLESS, WATCH_METHOD| Constructor and Description |
|---|
Exists() |
| Modifier and Type | Method and Description |
|---|---|
Sequence |
call(XPathContext context,
Sequence[] arguments)
Evaluate the expression
|
boolean |
effectiveBooleanValue(XPathContext c)
Evaluate the function in a boolean context
|
BooleanValue |
evaluateItem(XPathContext context)
Evaluate the function
|
ExpressionCompiler |
getExpressionCompiler()
Return the compiler of the Exists expression
|
int |
getImplementationMethod()
An implementation of Expression must provide at least one of the methods evaluateItem(), iterate(), or process().
|
ExistsAdjunct |
getStreamingAdjunct()
Get a class that supports streamed evaluation of this expression
|
boolean |
isNegatable(ExpressionVisitor visitor)
Check whether this specific instance of the expression is negatable
|
Expression |
negate()
Return the negation of the expression
|
Expression |
optimize(ExpressionVisitor visitor,
ExpressionVisitor.ContextItemType contextItemType)
Perform optimisation of an expression and its subexpressions.
|
checkArgumentsaddContextDocumentArgument, addDocToPathMap, bindStaticContext, computeCardinality, computeSpecialProperties, copy, equalOrNull, equals, getContextNode, getConvertingCallable, getDefaultArgumentNode, getDetails, getErrorCodeForTypeErrors, getFunctionItemType, getItemType, getOperation, getRequiredType, iterateSubExpressionInfo, makeSystemFunction, setDetails, useContextItemAsDefaultaddExternalFunctionCallToPathMap, checkArgumentCount, explain, getArguments, getDisplayName, getExpressionName, getFunctionName, getNumberOfArguments, hashCode, iterateSubExpressions, preEvaluate, promote, replaceSubExpression, setArguments, setFunctionName, simplify, simplifyArguments, toString, typeCheckaddToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, checkPermittedContents, computeDependencies, computeStaticProperties, doPromotion, dynamicError, evaluateAsString, evaluatePendingUpdates, explain, getCardinality, getColumnNumber, getColumnNumber, getConstructType, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getStreamability, getSystemId, getSystemId, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterate, iterateEvents, markTailFunctionCalls, process, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toPattern, toStreamingPattern, typeErrorpublic int getImplementationMethod()
SystemFunctionCallgetImplementationMethod in class SystemFunctionCallExpression.ITERATE_METHOD or Expression.EVALUATE_METHOD or
Expression.PROCESS_METHODpublic boolean isNegatable(ExpressionVisitor visitor)
isNegatable in interface Negatablepublic Expression negate()
public Expression optimize(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType) throws XPathException
This method is called after all references to functions and variables have been resolved to the declaration of the function or variable, and after all type checking has been done.
optimize in class SystemFunctionCallvisitor - an expression visitorcontextItemType - the static type of "." at the point where this expression is invoked.
The parameter is set to null if it is known statically that the context item will be undefined.
If the type of the context item is not known statically, the argument is set to
Type.ITEM_TYPEXPathException - if an error is discovered during this phase
(typically a type error)public BooleanValue evaluateItem(XPathContext context) throws XPathException
evaluateItem in class Expressioncontext - The context in which the expression is to be evaluatedXPathException - if any dynamic error occurs evaluating the
expressionpublic boolean effectiveBooleanValue(XPathContext c) throws XPathException
effectiveBooleanValue in class Expressionc - The context in which the expression is to be evaluatedXPathException - if any dynamic error occurs evaluating the
expressionpublic Sequence call(XPathContext context, Sequence[] arguments) throws XPathException
call in interface Callablecontext - the dynamic evaluation contextarguments - the values of the arguments, supplied as SequenceIteratorsXPathException - if a dynamic error occurs during the evaluation of the expressionpublic ExpressionCompiler getExpressionCompiler()
getExpressionCompiler in class Expressionpublic ExistsAdjunct getStreamingAdjunct()
getStreamingAdjunct in class ExpressionCopyright (c) 2004-2013 Saxonica Limited. All rights reserved.